CN116478447B

CN116478447B - Modified regenerant of polyester elastomer and application thereof

Info

Publication number: CN116478447B
Application number: CN202310738661.3A
Authority: CN
Inventors: 姜修磊; 余加保; 马云飞; 张磊; 吴梦琳
Original assignee: Suzhou Shensai New Materials Co ltd
Current assignee: Suzhou Shensai New Materials Co ltd
Priority date: 2023-06-21
Filing date: 2023-06-21
Publication date: 2023-08-29
Anticipated expiration: 2043-06-21
Also published as: CN116478447A

Abstract

The invention relates to a modified regenerant of a polyester elastomer and application thereof, belonging to the technical field of plastic regeneration foaming molding. The invention provides a modified regenerant of a polyester elastomer, wherein the components of the modified regenerant comprise an activating agent, a branching agent, a chain extender and a blocking agent, and the components of the blocking agent comprise a foaming capsule carrier and an epoxy polymer encapsulated in the foaming capsule carrier; when the modified regenerant is used for regenerating the polyester elastomer return material, based on a branching-chain extension-end capping strategy, the polyester elastomer, the activating agent and the branching agent are firstly mixed to obtain a raw material A, then the chain extension agent and the end capping agent are mixed to obtain a raw material B, finally the raw material A is added into a main hopper of a screw extruder, the raw material B is added into a side feeding hopper of the screw extruder, and the raw material B is extruded through a screw reaction, so that the regenerated polyester elastomer with good foaming performance for foaming can be obtained, and the effective recycling of the polyester elastomer return material is realized.

Description

Modified regenerant of polyester elastomer and application thereof

Technical Field

The invention relates to a modified regenerant of a polyester elastomer and application thereof, belonging to the technical field of plastic regeneration foaming molding.

Background

Thermoplastic polyester elastomer (TPEE) belongs to high-performance engineering grade elastomer and has excellent comprehensive performance and is widely applied to various fields, but on one hand, the TPEE has complex production process, low productivity and high price, which leads to continuous expansion of supply and demand gaps, and on the other hand, the TPEE contains a large amount of ester bonds, and degradation occurs in repeated processing processes for many times, so that the performance is greatly reduced, and a large amount of water gap materials and leftover materials are generated in injection molding and foaming processing and can only be treated as common plastics, thereby further increasing the productivity gaps.

At present, thermoplastic polyester elastomer recycle is an effective way to solve the productivity gap. However, existing thermoplastic polyester elastomer recycle processes still have some drawbacks. For example, in the patent application document with publication number CN111978686a, thermoplastic polyester elastomer recycled material and auxiliary agents such as glass fiber, inorganic filler, antioxidant, heat stabilizer and chain extender are mixed and extruded to obtain regenerated thermoplastic polyester elastomer, and the regeneration process combines the regeneration process and the modification process, so that the processing process is simplified, and the processing cost is saved. Therefore, it is desirable to find a recycling material that can be used in a foamed polyester elastomer recycling process to achieve efficient green recycling of thermoplastic polyester elastomer recycling.

Disclosure of Invention

In order to solve the defects, the invention provides a modified regenerant for a polyester elastomer, wherein the components of the modified regenerant comprise an activating agent, a branching agent, a chain extender and a blocking agent; the components of the end-capping agent comprise a foamed capsule carrier and an epoxy-based polymer encapsulated in the foamed capsule carrier.

In one embodiment of the invention, the modified regenerant consists of an activator, a branching agent, a chain extender and a capping agent; the end-capping agent consists of a foaming capsule carrier and an epoxy-based polymer encapsulated in the foaming capsule carrier.

In one embodiment of the present invention, in the modifying and regenerating agent, the mass ratio of the activating agent, the branching agent, the chain extender and the end capping agent is 0.05 to 0.1: 1-3: 1-5: 0.5 to 1.

In one embodiment of the present invention, in the end-capping agent, the mass ratio of the foamed capsule carrier to the epoxy-based polymer is 1: 1-2.

In one embodiment of the present invention, the method for preparing the end-capping agent comprises: and mixing the foaming capsule carrier and the epoxy polymer, and then stirring and adsorbing to obtain the end capping agent.

In one embodiment of the present invention, the method for preparing the end-capping agent comprises: and mixing the foaming capsule carrier and the epoxy polymer, and stirring and adsorbing for 10-120 min under the conditions that the vacuum degree is less than-0.08 Pa and the rotating speed is 20-100 rpm to obtain the end capping agent.

In one embodiment of the invention, the material of the foamed capsule carrier is thermoplastic polyester elastomer (TPEE).

In one embodiment of the present invention, the thermoplastic polyester elastomer has a pore size of 10 to 50 μm, and the thermoplastic polyester elastomer is prepared into particles having a size of 3 to 5mm, and then the capping agent is prepared.

In one embodiment of the invention, the epoxy-based polymer is a monofunctional epoxy-based polymer.

In one embodiment of the invention, the monofunctional epoxy-based polymer comprises gamma-glycidoxypropyl trimethoxysilane (CAS: 2530-83-8), glycidyl methacrylate (CAS: 106-91-2), and/or 1, 2-epoxydodecane (CAS: 2855-19-8).

In one embodiment of the invention, the components of the activator comprise sodium borohydride and sodium carbonate.

In one embodiment of the invention, the activator consists of sodium borohydride and sodium carbonate.

In one embodiment of the present invention, the mass ratio of sodium borohydride to sodium carbonate in the activator is 1:0.5 to 1.

In one embodiment of the invention, the branching agentThe chemical structural formula of (C) is R- (NCO) _n The method comprises the steps of carrying out a first treatment on the surface of the Wherein R is an alkyl group, an aryl group or an alicyclic group, and n is an integer of 2 to 4.

In one embodiment of the invention, the branching agent comprises diphenylmethane diisocyanate (CAS: 101-68-8), dimethylisoxazoletetraisocyanate (CAS: 131825-41-7), dicyclohexylmethane-4, 4 '-diisocyanate (CAS: 5124-30-1), isophorone diisocyanate (CAS: 4098-71-9) and/or triphenylmethane-2, 2' -dimethyl-3, 3', 5' -tetraisocyanate (CAS: 28886-07-9).

In one embodiment of the invention, the chain extender has the chemical formulaThe method comprises the steps of carrying out a first treatment on the surface of the Wherein Y is an aliphatic hydrocarbon group, X is an aromatic hydrocarbon group or an aliphatic hydrocarbon group, and m is an integer of 0 to 2.

In one embodiment of the invention, the chain extender comprises 2,2' -methylenebis [ (4, S) -4-phenyl-2-oxazoline ] (CAS: 132098-59-0), (S, S) - (-) -2,2' -isopropylidene bis (4-tert-butyl-2-oxazoline) (CAS: 131833-93-7) and/or (S, S) -2,2' -isopropylidene bis (4-phenyl-2-oxazoline) (CAS: 131457-46-0).

In one embodiment of the invention, the polyester elastomer is a polyester elastomer return. The polyester elastomer return material refers to a non-crosslinked polyester elastomer which does not contain inorganic filler after at least one molding process. In order to ensure that the recycled polyester elastomer can be used for foaming and has no influence on the foaming process, the recycled material cannot contain inorganic filler and cannot be crosslinked, because the crosslinked polyester elastomer cannot be subjected to secondary melt processing.

In one embodiment of the invention, the molding process is a thermoplastic molding process; the thermoplastic molding process includes injection molding, foam molding, extrusion molding, and/or compression molding.

The invention also provides a regenerated polyester elastomer for foaming, and the components of the regenerated polyester elastomer for foaming comprise the polyester elastomer and the modified regenerating agent.

In one embodiment of the present invention, the mass ratio between the polyester elastomer and the modified regenerant is 90 to 98: 2.55-9.1.

In one embodiment of the present invention, the method for producing the recycled polyester elastomer for foaming comprises the steps of: and mixing the polyester elastomer and the modified regenerant, and extruding to obtain the regenerated polyester elastomer for foaming.

In one embodiment of the present invention, the method for producing the recycled polyester elastomer for foaming comprises the steps of: mixing a polyester elastomer, an activating agent and a branching agent to obtain a raw material A; mixing a chain extender and a blocking agent to obtain a raw material B; and (3) adding the raw material A into a main hopper of a screw extruder, adding the raw material B into a side feeding hopper of the screw extruder, and performing screw reaction extrusion to obtain the regenerated polyester elastomer for foaming.

In one embodiment of the invention, the polyester elastomer is a polyester elastomer return. The polyester elastomer return material refers to a non-crosslinked polyester elastomer which does not contain inorganic filler after at least one molding process.

In one embodiment of the present invention, the recycled polyester elastomer is crushed to a size of 1 to 10 mesh and dried to a water content of less than 0.1%, and then the recycled polyester elastomer for foaming is prepared.

In one embodiment of the invention, the screw extruder has a screw aspect ratio greater than 40.

The invention also provides a foaming product which is obtained by foaming the regenerated polyester elastomer for foaming.

In one embodiment of the invention, the foaming is physical foaming or chemical foaming.

In one embodiment of the invention, the physical foaming is: placing the regenerated polyester elastomer for foaming in a foaming mold with the mold cavity temperature being the foaming temperature, and introducing a physical foaming agent into the mold cavity until the pressure in the mold cavity reaches the foaming pressure; continuously placing the regenerated polyester elastomer for foaming in a die cavity with the pressure being the foaming pressure and the temperature being the foaming temperature until the physical foaming agent reaches the dissolution balance in the regenerated polyester elastomer for foaming; and releasing the pressure in the die cavity to the ambient pressure at a pressure release rate, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foaming material.

In one embodiment of the invention, the foaming temperature is 120-190 ℃; the foaming pressure is 10-20 MPa; the time for reaching the dissolution balance is 90-180 min; the pressure relief rate is 5-20 MPa/s.

The invention also provides application of the modified regenerant or the regenerated polyester elastomer for foaming in preparation of a foaming product.

The technical scheme of the invention has the following advantages:

1. the invention provides a modified regenerant of a polyester elastomer, wherein the components of the modified regenerant comprise an activating agent, a branching agent, a chain extender and a blocking agent, and the components of the blocking agent comprise a foaming capsule carrier and an epoxy polymer encapsulated in the foaming capsule carrier; when the modified regenerant is used for regenerating the polyester elastomer return material, based on a branching-chain extension-end capping strategy, the polyester elastomer, the activating agent and the branching agent are firstly mixed to obtain a raw material A, then the chain extension agent and the end capping agent are mixed to obtain a raw material B, finally the raw material A is added into a main hopper of a screw extruder, the raw material B is added into a side feeding hopper of the screw extruder, and the raw material B is extruded through a screw reaction, so that the regenerated polyester elastomer with good foaming performance for foaming can be obtained, and the effective recycling of the polyester elastomer return material is realized.

Specifically, after melt processing, the polyester elastomer returns are degraded in molecular chains, so that the polyester elastomer returns contain a large number of active end groups including hydroxyl groups, carboxyl groups and the like, and currently, a polyfunctional epoxy-based polymer is generally selected as a chain extender in the market to perform chain extension extrusion reaction on the returns to realize regeneration of the polyester elastomer, however, as the epoxy groups of the polyfunctional epoxy-based polymer have high activity and can react with both hydroxyl groups and carboxyl groups, the polyfunctional epoxy-based polymer has too high functionality (for example, the Joncryl ADR4400 active group is 5,Joncryl ADR4468 active group is 9), and the chain extender itself plays the role of a cross-linking agent, so that a cross-linking structure is generated in the regenerated polyester elastomer obtained by regenerating the returns by using the polyfunctional epoxy-based polymer as the chain extender, and local gel appears, thereby influencing the reuse of the regenerated polyester elastomer in the fields of foaming and the like.

The modified regenerant disclosed by the invention is characterized in that part of carboxyl in the return material is converted into hydroxyl through the activating agent to be a main functional group of a molecular chain, so that the reaction probability is improved, branching and chain extension of the return material are carried out step by step, the gel phenomenon caused by one-step reaction in the chain extension process is effectively avoided, finally, the epoxy polymer is encapsulated by using the foaming capsule carrier, the contact reaction time of the epoxy polymer and the return material is delayed, the epoxy polymer in the end-capping agent and the chain extender are prevented from performing polymerization, and further, the generation of a crosslinking structure in the regenerated polyester elastomer is effectively avoided. The modified regenerant disclosed by the invention has the advantages that the polyester elastomer return material is tackified and regenerated through a branching-chain extension-end capping strategy, the foaming uniformity is prevented from being influenced by the gel problem caused by independently using the chain extender in the return material regeneration process while the good foaming property is effectively improved, and the problem of poor stability of the regenerated material is solved and the service life of a product is prolonged by carrying out end capping treatment on the chain active end group, so that the modified regenerant disclosed by the invention can be used for regenerating the polyester elastomer return material, thereby endowing the regenerated polyester elastomer with good foaming property, realizing the effective recycling of the polyester elastomer return material, effectively relieving the productivity gap of a high-performance engineering elastomer, and reducing carbon emission and assisting double carbon targets through recycling.

Further, the chemical structural formula of the branching agent is R- (NCO) _n The method comprises the steps of carrying out a first treatment on the surface of the Wherein R is an alkyl group, an aryl group or an alicyclic group, and n is an integer of 2 to 4. After the activation treatment of the first step, the branching structure can be realized to the greatest extent by selecting a branching agent with higher reactivity to hydroxyl, and the chemical structural formula is R- (NCO) _n The branching agent of (2) is very reactive towards hydroxyl groups and is therefore selected to have the formula R- (NCO) _n Is helpful in achieving branching of the polyester elastomer return.

Further, the branching agent includes diphenylmethane diisocyanate, dimethylisoxazole tetraisocyanate, dicyclohexylmethane-4, 4 '-diisocyanate, isophorone diisocyanate, and/or triphenylmethane-2, 2' -dimethyl-3, 3', 5' -tetraisocyanate. The reactivity of isocyanate when reacting with compounds containing active hydrogen such as hydroxyl and carboxyl depends on the group connected with the hydroxyl or carboxyl, if the connected group is electron donating, the more electronegativity is, the simpler the transfer of active hydrogen atoms and the higher the reactivity; the conjugation of carbon-oxygen double bonds in carboxyl groups reduces electron cloud density, so that electronegativity of oxygen atoms connected with active hydrogen is weakened, and therefore, no hydroxyl group is high in reactivity, and at the moment, the branching agent can preferentially carry out branching reaction with a large number of main functional groups, namely hydroxyl groups, so that a branched structure is formed.

Further, the chain extender has a chemical structural formula ofThe method comprises the steps of carrying out a first treatment on the surface of the Wherein Y is an aliphatic hydrocarbon group, X is an aromatic hydrocarbon group or an aliphatic hydrocarbon group, and m is an integer of 0 to 2. The hydroxyl which does not participate in the branching reaction on the activated material is heated and sheared by the screw rod and is converted into a more stable carboxyl structure under the action of hot oxygen, so that the chain extender with high reactivity to carboxyl is selected in the chain extension reaction, the quick chain extension reaction is facilitated, and the chemical structural formula is->The chain extender of (2) has very high reactivity to hydroxyl groups, and therefore, the chemical formula is selected to be +.>The chain extender of (2) helps to achieve rapid chain extension of the polyester elastomer return.

Further, the epoxy-based polymer is a monofunctional epoxy-based polymer. In the regeneration process of the recycled material, the material exposes more active end groups due to multiple times of melt processing, and the active end groups are easy to absorb water to further promote the degradation of a molecular chain, so that the stability of the recycled material is poor, and therefore, the active end groups are required to be subjected to end capping treatment, so that the stability of the recycled material is improved. The invention selects the high-activity monofunctional epoxy polymer to carry out end capping treatment on the feed back end group, so that the stability of the reclaimed material can be obviously improved.

Further, the material of the foaming capsule carrier is thermoplastic polyester elastomer (TPEE). The TPEE-based foaming capsule carrier is selected to effectively avoid the influence of other resins introduced into the system on the foamability of the regenerated polyester elastomer.

2. The invention provides a regenerated polyester elastomer for foaming, which comprises polyester elastomer and a modified regenerating agent, wherein the modified regenerating agent comprises an activating agent, a branching agent, a chain extender and a blocking agent, and the blocking agent comprises a foaming capsule carrier and an epoxy polymer encapsulated in the foaming capsule carrier; the preparation method of the regenerated polyester elastomer for foaming comprises the following steps: mixing a polyester elastomer, an activating agent and a branching agent to obtain a raw material A; mixing a chain extender and a blocking agent to obtain a raw material B; and (3) adding the raw material A into a main hopper of a screw extruder, adding the raw material B into a side feeding hopper of the screw extruder, and performing screw reaction extrusion to obtain the regenerated polyester elastomer for foaming. The regenerated polyester elastomer for foaming has good foaming performance, can effectively realize recycling of the polyester elastomer return material, effectively relieves the productivity gap of the high-performance engineering elastomer, and reduces carbon emission and power-assisted double carbon targets through recycling.

Further, the recycled polyester elastomer is crushed to a size of 1-10 meshes, dried to a water content of less than 0.1%, and then subjected to preparation of the regenerated polyester elastomer for foaming. The recycling process of the polyester elastomer is essentially reactive extrusion, so that stable blanking is very important, and meanwhile, the smaller the size of the recycled material particles, the more uniformly mixed with the reactive auxiliary agent, so that the reaction is facilitated. In the regeneration extrusion of the polyester elastomer return material, as the polyester is very sensitive to moisture, trace water can lead the polyester to be rapidly degraded under the high-temperature and high-shear condition, so that the performance is attenuated, and therefore, the control of the moisture content of the return material is very critical.

Further, the screw extruder has a screw aspect ratio greater than 40. In the polyester elastomer recycle regeneration process, various auxiliary agents are involved in the reaction with the polyester elastomer, so that the melt mixing residence time between the auxiliary agent and the resin needs to be ensured to ensure the completion of the reaction, and therefore, a screw with a large length-diameter ratio needs to be selected.

Drawings

Fig. 1: shear loss angle test of the recycled polyester elastomer obtained in example 4.

Fig. 2: cole-Cole diagram of the recycled polyester elastomer obtained in example 4.

Fig. 3: foam physical image of the recycled polyester elastomer obtained in example 4.

Fig. 4: electron micrograph of the recycled polyester obtained in example 4 after elastic foaming.

Fig. 5: electron micrograph of the regenerated foamed elastomer obtained in comparative example 1.

Fig. 6: electron micrograph of the regenerated foamed elastomer obtained in comparative example 2.

Fig. 7: comparative example 6 in-situ sample was low drop-out photographs during extrusion processing.

Fig. 8: comparative example 7 a photo of the branching agent rapidly reacts upon processing.

Fig. 9: comparative example 8 cross-linked photographs of the bars when extruded.

Fig. 10: shear loss angle plot of the recycled polyester elastomer obtained in comparative example 9.

Fig. 11: comparative example 9 shows a foam pattern of the regenerated polyester elastomer.

Fig. 12: comparative example 9 a foam electron micrograph of the regenerated polyester elastomer obtained.

Fig. 13: shear loss angle of the regenerated polyester elastomer obtained in comparative example 10.

Fig. 14: physical image of the recycled polyester elastomer foam obtained in comparative example 10.

Fig. 15: comparative example 10 was obtained by electron micrograph of a recycled polyester elastomer foam.

Detailed Description

The following examples are provided for a better understanding of the present invention and are not limited to the preferred embodiments described herein, but are not intended to limit the scope of the invention, any product which is the same or similar to the present invention, whether in light of the present teachings or in combination with other prior art features, falls within the scope of the present invention.

The following examples do not identify specific experimental procedures or conditions, which may be followed by procedures or conditions of conventional experimental procedures described in the literature in this field. The reagents or apparatus used were conventional reagent products commercially available without the manufacturer's knowledge.

The polyester elastomer return materials involved in the following embodiments are injection molding water gap materials, foaming leftover materials and plate broken materials respectively, and are purchased from 91 regenerated nets; sodium borohydride and sodium carbonate referred to in the examples below were purchased from the aara Ding Huaxue reagent; diphenylmethane diisocyanate, dimethylisoxazole tetraisocyanate, triphenylmethane-2, 2' -dimethyl-3, 3', 5' -tetraisocyanate referred to in the examples below were purchased from Wanhua chemistry; 2,2' -methylenebis [ (4, S) -4-phenyl-2-oxazoline ], (S, S) - (-) -2,2' -isopropylidenebis (4-tert-butyl-2-oxazoline), (S, S) -2,2' -isopropylidenebis (4-phenyl-2-oxazoline) as referred to in the following examples, purchased from Shanghai regular script and biosciences, inc.; the foaming capsule carrier TPEE-0210 referred to in the following examples was purchased from the material science and technology company of chu-zhi-shan, south kyo; gamma-glycidoxypropyl trimethoxysilane, glycidyl methacrylate, 1,2 epoxydodecane, referred to in the examples below, were purchased from jekcal chemical company, ngzhou.

Example 1: modified regenerant for polyester elastomer

The embodiment provides a modified regenerant for a polyester elastomer, wherein the modified regenerant comprises the following components in percentage by mass of 0.05:1:1:0.5 activator, triphenylmethane-2, 2 '-dimethyl-3, 3',5 '-tetraisocyanate (branching agent), 2' -methylenebis [ (4, s) -4-phenyl-2-oxazoline ] (chain extender) and end capping agent;

wherein the activator comprises the following components in percentage by mass: 0.5 of sodium borohydride and sodium carbonate, and the preparation method of the activator comprises the following steps: mixing sodium borohydride and sodium carbonate, and performing ball milling on the mixture on a ball mill for 1min to obtain an activator;

the end capping agent comprises the following components in percentage by mass: 1 (foaming capsule carrier) and gamma-glycidol ether oxypropyl trimethoxy silane, wherein the preparation method of the end capping agent comprises the following steps: TPEE-0210 and gamma-glycidoxypropyl trimethoxysilane are mixed and then stirred (10 rpm) in a vacuum (vacuum degree-0.09 Pa) stirrer for 30min to obtain the end capping agent.

Example 2: modified regenerant for polyester elastomer

The embodiment provides a modified regenerant for a polyester elastomer, wherein the modified regenerant comprises the following components in percentage by mass: 2:3:0.7 of an activator, dimethyl isoxazole tetraisocyanate (branching agent), (S, S) - (-) -2,2' -isopropylidene bis (4-tert-butyl-2-oxazoline) (chain extender) and a blocking agent;

Wherein the activator comprises the following components in percentage by mass: 0.8 of sodium borohydride and sodium carbonate, wherein the preparation method of the activator comprises the following steps: mixing sodium borohydride and sodium carbonate, and performing ball milling on the mixture on a ball mill for 1min to obtain an activator;

the end capping agent comprises the following components in percentage by mass: 1.5 TPEE-0210 (foam capsule carrier) and glycidyl methacrylate, the preparation method of the end capping agent is as follows: after TPEE-0210 and glycidyl methacrylate were mixed, the mixture was stirred in a vacuum (vacuum degree-0.08 Pa) stirrer (10 rpm) and adsorbed for 30 minutes to obtain a blocking agent.

Example 3: modified regenerant for polyester elastomer

The embodiment provides a modified regenerant for a polyester elastomer, wherein the modified regenerant comprises the following components in percentage by mass: 2:5:1, diphenylmethane diisocyanate (branching agent), (S, S) -2,2' -isopropylidene bis (4-phenyl-2-oxazoline) (chain extender) and end capping agent;

wherein the activator comprises the following components in percentage by mass: 1 and sodium carbonate, wherein the preparation method of the activator comprises the following steps: mixing sodium borohydride and sodium carbonate, and performing ball milling on the mixture on a ball mill for 1min to obtain an activator;

the end capping agent comprises the following components in percentage by mass: 2 (foaming capsule carrier) and gamma-glycidol ether oxypropyl trimethoxy silane, wherein the preparation method of the end capping agent comprises the following steps: after TPEE-0210 and glycidyl methacrylate were mixed, the mixture was stirred in a vacuum (vacuum degree-0.08 Pa) stirrer (10 rpm) and adsorbed for 30 minutes to obtain a blocking agent.

Example 4: regenerated polyester elastomer for foaming

The embodiment provides a recycled polyester elastomer for foaming, which comprises the following components in percentage by mass: 2.55 and a modified regenerant of example 1, wherein the preparation method of the regenerated polyester elastomer for foaming comprises the following steps: cleaning, drying, crushing and sieving the injection molding nozzle material to obtain a treated injection molding nozzle material with the mesh number of 4-6 meshes and the water content of 0.078%; mixing the treated injection molding water gap material, an activating agent and a branching agent in a high-speed mixer for 5min to obtain a raw material A; mixing a chain extender and a blocking agent in a high-speed mixer for 2min to obtain a raw material B; adding a raw material A into a main hopper of a screw extruder (the length-diameter ratio of the screw is 46, the rotation speed of a main machine is 200rpm, the rotation speed of a main discharging opening is 12rpm, and the rotation speed of a side feeding opening is 8 rpm), adding a raw material B into a side feeding hopper of the screw extruder, and extruding into a spline with the diameter of 8mm and the length of 10cm through screw reaction at 230 ℃ to obtain a regenerated polyester elastomer for foaming; wherein, the mass ratio of the treated injection molding water gap material, the activating agent, the branching agent, the chain extender and the end capping agent is 97.45:0.05:1:1:0.5.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 2432.5Pa.s, and the complex viscosity of the polyester elastomer after aging is 2041.3Pa.s. FIG. 1 is a plot of shear loss angle with no plateau region present, indicating that there is no crosslinked structure in the melt structure. FIG. 2 is a graph of Cole-Cole showing the presence of long chain branches as a result of the upward warp of the arc. This result demonstrates that the molecular chain length is effectively extended by the branched chain extension strategy, the elastomer viscosity is increased, and no crosslinked structure is formed.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming ratio of the foamed elastomer was 17 times. FIG. 3 is a diagram of a foamed elastomer with uniform internal foaming and no foam cracking. Fig. 4 is an electron micrograph of the foamed elastomer, and it can be seen that the foamed cells are uniform. This result demonstrates that the produced polyester elastomer reclaimed material has excellent foaming property.

Example 5: regenerated polyester elastomer for foaming

The embodiment provides a regenerated polyester elastomer for foaming, which comprises the following components in percentage by mass: 5.78 and a modified regenerant of example 2, wherein the preparation method of the regenerated polyester elastomer for foaming comprises the following steps: cleaning, drying, crushing and sieving the injection molding nozzle material to obtain a treated injection molding nozzle material with the mesh number of 4-6 meshes and the water content of 0.078%; mixing the treated injection molding water gap material, an activating agent and a branching agent in a high-speed mixer for 5min to obtain a raw material A; mixing a chain extender and a blocking agent in a high-speed mixer for 2min to obtain a raw material B; adding a raw material A into a main hopper of a screw extruder (the length-diameter ratio of the screw is 46, the rotation speed of a main machine is 200rpm, the rotation speed of a main discharging opening is 12rpm, and the rotation speed of a side feeding opening is 8 rpm), adding a raw material B into a side feeding hopper of the screw extruder, and extruding into a spline with the diameter of 8mm and the length of 10cm through screw reaction at 230 ℃ to obtain a regenerated polyester elastomer for foaming; wherein, the mass ratio of the treated injection molding water gap material, the activating agent, the branching agent, the chain extender and the end capping agent is 94.22:0.08:2:3:0.7.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 2702.1Pa.s, and the complex viscosity of the polyester elastomer after aging is 2396.3Pa.s. This result demonstrates that the present example recycling formulation can effectively tackify polyester elastomer returns and increase melt strength.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming ratio of the foaming elastomer is 18 times, and the foaming elastomer is not damaged. This result demonstrates that the produced polyester elastomer reclaimed material has excellent foaming property.

Example 6: regenerated polyester elastomer for foaming

The embodiment provides a regenerated polyester elastomer for foaming, which comprises the following components in percentage by mass: 8.06 and a modified regenerant of example 3, wherein the preparation method of the regenerated polyester elastomer for foaming comprises the following steps: cleaning, drying, crushing and sieving the injection molding nozzle material to obtain a treated injection molding nozzle material with the mesh number of 4-6 meshes and the water content of 0.078%; mixing the treated injection molding water gap material, an activating agent and a branching agent in a high-speed mixer for 5min to obtain a raw material A; mixing a chain extender and a blocking agent in a high-speed mixer for 2min to obtain a raw material B; adding a raw material A into a main hopper of a screw extruder (the length-diameter ratio of the screw is 44, the rotating speed of a main machine is 200rpm, the rotating speed of a main discharging opening is 12rpm, and the rotating speed of a side feeding opening is 8 rpm), adding a raw material B into a side feeding hopper of the screw extruder, and extruding into a spline with the diameter of 8mm and the length of 10cm through screw reaction at 230 ℃ to obtain a regenerated polyester elastomer for foaming; wherein, the mass ratio of the treated injection molding water gap material, the activating agent, the branching agent, the chain extender and the end capping agent is 91.94:0.06:2:5:1.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 4402.7Pa.s, and the complex viscosity of the polyester elastomer after aging is 3101.3Pa.s. This result demonstrates that the regeneration formulation of this example can effectively increase the return viscosity, and that increasing the amount of chain extender can greatly increase the melt viscosity.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming multiplying power of the foaming elastomer is 16 times, and the foaming elastomer is not damaged. This result demonstrates that the produced polyester elastomer reclaimed material has excellent foaming property.

Comparative example 1: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which is obtained by adding no branching agent to the recycled polyester elastomer for foaming in the base of example 2.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 1692.9Pa.s, and the complex viscosity of the polyester elastomer after aging is 990.7Pa.s. This result demonstrates that the lack of branching agent is effective in the tackifying effect of the polyester elastomer return because the chain extender is less reactive with hydroxyl groups, resulting in an insignificant tackifying effect.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming of the foaming elastomer is uneven, and the foaming multiplying power can not be tested. Fig. 5 is an electron micrograph of a foamed elastomer with few and non-uniform cells, illustrating that melt strength is difficult to maintain foaming. This result indicates that the foaming property of the produced polyester elastomer reclaimed material is poor.

Comparative example 2: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which is obtained by adding no chain extender to the recycled polyester elastomer for foaming in the base of example 3.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 1302.7Pa.s, and the complex viscosity of the polyester elastomer after aging is 785.3Pa.s. This result demonstrates that the recycle cannot be effectively regeneratively tackified without the addition of a chain extender.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming of the foaming elastomer is uneven, and the foaming multiplying power can not be tested. Fig. 6 is an electron micrograph of a foamed elastomer with few and non-uniform cells, illustrating that melt strength is difficult to maintain foaming. This result indicates that the foaming property of the produced polyester elastomer reclaimed material is poor.

Comparative example 3: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which is obtained by adding no activator to the recycled polyester elastomer for foaming in the base of example 3.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 3015.7Pa.s, and the complex viscosity of the polyester elastomer after aging is 185.3Pa.s. This result indicates that the polyester elastomer which has not been activated fails to form a large amount of branched structure and causes a large amount of end-capping agent to react with the branching agent or the like to lose the end-capping effect, resulting in poor aging properties.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming ratio of the foaming elastomer is 10 times. In the absence of an activation step, the branching agent needs to undergo a bid polymerization reaction with the crosslinking agent, resulting in incomplete branching and accompanying internal partial crosslinking, although the melt viscosity is not significantly reduced, high-rate foaming cannot be achieved, and only 10-time foaming rate can be achieved at maximum. This result indicates that the foaming property of the produced polyester elastomer reclaimed material is poor.

Comparative example 4: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which is obtained by adding no end-capping agent to the recycled polyester elastomer for foaming in example 3.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 4715.9Pa.s, and the complex viscosity of the polyester elastomer after aging is 785.1Pa.s. This result demonstrates that the water-oxygen aging resistance of the reclaimed material is significantly reduced by 85% over an aging cycle viscosity after the absence of the capping agent.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming multiplying power of the foaming elastomer is 12.3 times, mainly because the reactive end group which is not subjected to end capping treatment is locally degraded under the high-temperature and high-pressure foaming condition, so that the melt strength is reduced in the foaming process, and the foaming multiplying power is reduced. This result indicates that the foaming property of the produced polyester elastomer reclaimed material is poor.

Comparative example 5: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which is obtained by using only gamma-glycidyloxypropyl trimethoxysilane as a blocking agent without using a foam capsule carrier in the process of example 3.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 2015.7Pa.s, and the complex viscosity of the polyester elastomer after aging is 985.3Pa.s. This result suggests that the absence of encapsulating the capping agent resulted in the capping agent competing with the chain extender, making the regenerative tackifying effect poor, and that the capping agent failed to achieve the capping effect, resulting in poor aging resistance.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming ratio of the foaming elastomer was 9.8 times. Under the slow release effect of the foaming capsule carrier on the blocking agent, the blocking agent blocks the chain extender in a large amount, so that the chain extender is incomplete, the tackifying is not obvious, and the foaming multiplying power is difficult to rise. This result indicates that the foaming property of the produced polyester elastomer reclaimed material is poor.

Comparative example 6: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which comprises, based on example 3, a treated injection molding nozzle material, an activator, a branching agent, a chain extender and a capping agent in a mass ratio of 91.94:0.06:2:5:1 to 91.8:0.2:2:5:1, a recycled polyester elastomer for foaming was obtained.

As shown in fig. 7, since the activator is an alkaline substance, a large amount of activator causes molecular chain breakage, the extruded sample has almost no melt strength, and becomes a high-flow melt completely, and is directly agglomerated with low drop, and cannot be molded.

Comparative example 7: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which comprises, based on example 3, a treated injection molding nozzle material, an activator, a branching agent, a chain extender and a capping agent in a mass ratio of 91.94:0.06:2:5:1 is adjusted to 88.94:0.06:5:5:1, a recycled polyester elastomer for foaming was obtained.

As shown in FIG. 8, since the branching agent is a substance containing a large amount of active end groups, the branching agent is added into a high-temperature screw to rapidly react, a large amount of smoke is generated by intense reaction, and meanwhile, the melt forms an insoluble and infusible bulk phase structure, so that the screw cannot be extruded and molded.

Comparative example 8: regenerated polyester elastomer for foaming

The comparative example provides a recycled polyester elastomer for foaming, which comprises the following components in percentage by mass: 2.55 and a basf ADR4400 chain extender, wherein the preparation method of the regenerated polyester elastomer for foaming comprises the following steps: cleaning, drying, crushing and sieving the injection molding nozzle material to obtain a treated injection molding nozzle material with the mesh number of 4-6 meshes and the water content of 0.078%; mixing the treated injection molding water gap material and the Pasteur ADR4400 chain extender, then adding the mixture into a main hopper of a screw extruder (the length-diameter ratio of the screw is 46, the rotation speed of a main machine is 200rpm, and the rotation speed of a main feed opening is 12 rpm), and extruding the mixture into a spline with the diameter of 8mm and the length of 10cm through screw reaction at 230 ℃ to obtain a regenerated polyester elastomer for foaming; wherein, the mass ratio of the treated injection molding nozzle material to the Pasteur ADR4400 chain extender is 97.45:2.55.

as shown in FIG. 9, during extrusion, a severe crosslinking reaction occurred, and the bars from the extruder die had a large number of bubbles, and were not continuously processed.

Comparative example 9: regenerated polyester elastomer for foaming

The comparative example provides a recycled polyester elastomer for foaming, which comprises the following components in percentage by mass: 1 and a basf ADR4400 chain extender, wherein the preparation method of the regenerated polyester elastomer for foaming comprises the following steps: cleaning, drying, crushing and sieving the injection molding nozzle material to obtain a treated injection molding nozzle material with the mesh number of 4-6 meshes and the water content of 0.078%; mixing the treated injection molding water gap material and the Pasteur ADR4400 chain extender, then adding the mixture into a main hopper of a screw extruder (the length-diameter ratio of the screw is 46, the rotation speed of a main machine is 200rpm, and the rotation speed of a main feed opening is 12 rpm), and extruding the mixture into a spline with the diameter of 8mm and the length of 10cm through screw reaction at 230 ℃ to obtain a regenerated polyester elastomer for foaming; wherein, the mass ratio of the treated injection molding nozzle material to the Pasteur ADR4400 chain extender is 99:1.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 3472.1Pa.s, and the complex viscosity of the polyester elastomer after aging is 1756.1Pa.s. FIG. 10 is a plot of shear loss angle with distinct plateau regions showing the melt structure having a crosslinked structure. This result demonstrates that the comparative example regenerates the formulation to cause crosslinking of the molecular chains, while the viscosity is increased, but the performance structure is lost and localized gels appear.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming ratio of the foaming elastomer is 10 times. FIG. 11 is a diagram of a foamed elastomer showing the occurrence of cracking due to concentration of foaming stress caused by partial crosslinking, as a result of internal cracking in the foaming. Fig. 12 is an electron micrograph of a foamed elastomer, and it can be seen that the foamed cells are heterogeneous. This result indicates that the foaming property of the produced polyester elastomer reclaimed material is poor.

Comparative example 10: regenerated polyester elastomer for foaming

This comparative example provides a recycled polyester elastomer for foaming, which is obtained by substituting the process for producing a recycled polyester elastomer for foaming in example 1: cleaning, drying, crushing and sieving the injection molding nozzle material to obtain a treated injection molding nozzle material with the mesh number of 4-6 meshes and the water content of 0.078%; mixing the treated injection molding water gap material, an activating agent and a branching agent in a high-speed mixer for 5min to obtain a raw material A; mixing a chain extender and a blocking agent in a high-speed mixer for 2min to obtain a raw material B; raw material A and raw material B are mixed and then added into a main hopper of a screw extruder (the length-diameter ratio of the screw is 46, the rotation speed of a main machine is 200rpm, and the rotation speed of a main feed opening is 12 rpm), and the mixture is extruded into bars with the diameter of 8mm and the length of 10cm through screw reaction at 230 ℃ to obtain the regenerated polyester elastomer for foaming.

The prepared polyester elastomer reclaimed material was subjected to a rheology test (detection using a rheometer of the type TA RES G2) and an aging test (detection using an aging oven of the type RK-TH-150), and the rheology test conditions were: the aging test conditions at 180 ℃ and strain of 10% are: aging at 80deg.C with humidity of 95% RH for 48 hr. The detection result is as follows: the complex viscosity of the prepared regenerated polyester elastomer is 10472.1Pa.s, and the complex viscosity of the polyester elastomer after aging is 9756.1Pa.s. FIG. 13 is a plot of shear loss angle with distinct plateau regions showing the melt structure having a crosslinked structure. This result demonstrates that feeding together can effectively achieve the purpose of recycle regeneration and tackifying, but a great deal of crosslinking occurs in the molecular chains, and the thermoplastic is converted into thermosetting.

Placing the prepared polyester elastomer reclaimed material into a foaming mould (the size is 250 multiplied by 350 multiplied by 30 mm) with the mould cavity temperature of 135 ℃ (the foaming temperature), and introducing supercritical carbon dioxide into the mould cavity until the pressure in the mould cavity reaches 16MPa (the foaming pressure); placing the regenerated polyester elastomer for foaming in a die cavity with the pressure of 16MPa and the temperature of 135 ℃ for 120min, so that carbon dioxide reaches dissolution balance in the regenerated polyester elastomer material prepared for foaming; and (3) releasing the pressure in the die cavity to the ambient pressure at a pressure release rate of 10MPa/s, and inducing the nucleation and growth of cells to foam the regenerated polyester elastomer for foaming to obtain the foamed elastomer. The foaming ratio of the foaming elastomer is 13 times. FIG. 14 is a graphical representation of a foamed elastomer with a break in the middle of the foam illustrating non-uniformity in melt strength. Fig. 15 is an electron micrograph of the foamed elastomer, and it can be seen that the foamed cells are not uniform. This result indicates that the foaming property of the produced polyester elastomer reclaimed material is poor.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.

Claims

1. A modified regenerant for a polyester elastomer, which is characterized in that the components of the modified regenerant comprise an activating agent, a branching agent, a chain extender and a blocking agent; the components of the end-capping agent comprise a foaming capsule carrier and an epoxy-based polymer encapsulated in the foaming capsule carrier;

in the modified regenerant, the mass ratio of the activating agent to the branching agent to the chain extender to the end capping agent is 0.05-0.1: 1-3: 1-5: 0.5-1;

in the end-capping agent, the mass ratio of the foaming capsule carrier to the epoxy polymer is 1: 1-2;

the components of the activator comprise sodium borohydride and sodium carbonate;

the chemical structural formula of the branching agent is R- (NCO) _n The method comprises the steps of carrying out a first treatment on the surface of the Wherein R is an alkyl group, an aryl group or an alicyclic group, and n is an integer of 2 to 4;

the chemical structural formula of the chain extender isThe method comprises the steps of carrying out a first treatment on the surface of the Wherein Y is an aliphatic hydrocarbon group, X is an aromatic hydrocarbon group or an aliphatic hydrocarbon group, and m is an integer of 0 to 2;

the material of the foaming capsule carrier is thermoplastic polyester elastomer.

2. The modified regenerant of claim 1, wherein said capping agent is prepared by the process comprising: and mixing the foaming capsule carrier and the epoxy polymer, and then stirring and adsorbing to obtain the end capping agent.

3. The modified regenerant of claim 2, wherein said capping agent is prepared by the process of: and mixing the foaming capsule carrier and the epoxy polymer, and stirring and adsorbing for 10-120 min under the conditions that the vacuum degree is less than-0.08 Pa and the rotating speed is 20-100 rpm to obtain the end capping agent.

4. The modified recycling agent according to claim 3, wherein the thermoplastic polyester elastomer has a pore diameter of 10 to 50 μm, and the end-capping agent is prepared after preparing the thermoplastic polyester elastomer into particles having a size of 3 to 5 mm.

5. The modified regenerant of claim 1, wherein said epoxy-based polymer is a monofunctional epoxy-based polymer.

6. The modified regenerant of claim 5, wherein said monofunctional epoxy-based polymer comprises gamma-glycidoxypropyl trimethoxysilane, glycidyl methacrylate and/or 1, 2-epoxydodecane.

7. The modified regenerant of claim 1, wherein said branching agent comprises diphenylmethane diisocyanate, dimethylisoxazoletetraisocyanate, dicyclohexylmethane-4, 4 '-diisocyanate, isophorone diisocyanate and/or triphenylmethane-2, 2' -dimethyl-3, 3', 5' -tetraisocyanate.

8. The modified regenerant of claim 1, wherein said chain extender comprises 2,2' -methylenebis [ (4, S) -4-phenyl-2-oxazoline ], (S, S) - (-) -2,2' -isopropylidene bis (4-tert-butyl-2-oxazoline) and/or (S, S) -2,2' -isopropylidene bis (4-phenyl-2-oxazoline).

9. A recycled polyester elastomer for foaming, comprising a polyester elastomer and the modified recycling agent according to any one of claims 1 to 8.

10. The recycled polyester elastomer for foaming according to claim 9, wherein the mass ratio between the polyester elastomer and the modified recycling agent is 90 to 98: 2.55-9.1.

11. A foamed product characterized in that it is obtained by foaming the regenerated polyester elastomer for foaming according to claim 9 or 10.

12. Use of the modified recycling agent of any one of claims 1 to 8 or the recycled polyester elastomer for foaming of claim 9 or 10 for preparing a foamed product.